Using 3D printed heart models to prepare for heart surgery for babies

Mar.5, 2013

Doctors want as much information as possible when preparing to correct heart defects in pediatric patients. They read images from CT scans and use software to study abnormalities in three dimensions by moving a picture of the heart around on a computer screen to analyze and plan a surgical strategy.

But now, doctors could take the process one step further: using 3D printers doctors are printing out color-coded, 3D plastic models of a patients' heart.

At the Children's Heart Center at Phoenix Children's Hospital, Justin Ryan, a graduate student at Arizona State University shows how he models and 3D prints heart models. He takes the two-dimensional images from CT scans and sends it to a 3D printer to print out the model. The 3D printer, ZPrinter 650 from 3D Systems, could print out a heart model of one-year-old child in about three hours. The model is printed by shooting colored glue on layer by layer of plaster powder, forming the model according to the precise specifications of the data. "From there, we do a bit of post-processing, but in another hour after that, we can hand it off to the doctor. They can view it, and make their decisions on surgery." says Ryan.

Heart surgeries are very complicated operations, because baby's heart is very small, only about the size of a walnut. As child grows the heart is about the size of their fist. Each 3D printed heart model is assigned a different color, and the color coding could help medical teams better understand the tiny anatomical structures they will work with during surgery, says John Nigro, M.D., director of cardiothoracic surgery and co-director of the heart center.

Using a heart model to prepare for surgery is like finding your way with a GPS instead of a paper map, says Daniel Velez, M.D., a congenital heart surgeon at PCH. The real 3D model allows doctors to explain to the parents what they can do, what their plan is. Normally it is pretty hard for new parents to understand that their beautiful baby has a heart defect, but with a 3D printed heart model the doctors could help them to understand the nature of the defect, and young patients are likely to do better with support, says Stephen G. Pophal, M.D., division chief of pediatric cardiology at PCH. Pophal. "The major impact is that we will be able to teach people more about their heart problems. This makes it very simple."

ASU engineering professor David Frakes expects that very soon doctors could just use these 3D printed models to prepare their surgery, or bring them into the operating room.

Knowing more in advance could also cut down on the number of images needed as procedures are performed, lowering radiation exposure. The tough job of visualizing a defect in three dimensions based on a two-dimensional image—sort of like imagining what a house will look like based on architectural plans—would be eliminated, says Pophal. "If I had the model in my hand, I would save half the time, and have half of the worries."